Plastic bag with inlet valve



Jan. 10, 1967 KARL-HElNZ HONSEL ETAL 3,297,234

PLASTIC BAG WITH INLET VALVE 2 Sheets-Sheet l Filed July 6, 1965 auf.:am

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PLASTIC BAG WITH INLET VALVE 2 Sheets-Sheet 2 Filed July 6, 1965 FIG.7

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United States Patent O 3,297,234 PLASTIC BAG WITH INLET VALVE Karl-HeinzHonsel, Bielefeld, Paul Maurer, Beckum,

and Karl-Friedrich Duwe, Oberkassel, near Bonn, Germany, assignors toPSG Plastik-Sack G.m.b.I-I., Rosbach (Sieg), Manel, Germany, alimited-liability company of Germany Filed July 6, 1965, Ser. No.469,472 13 Claims. (Cl. 229-625) The invention relates to plastic bagsfor packaging solid materials, such as powdered and granular objects,having formed therein a valve structure which permits the materials tobe introduced and,which valve closes automatically to prevent the escapeof solid material. The invention is especially applicable to fillingplastic bags that are initially entirely closed save for the said valve.

Prior bags made of sheets or tubes of plastic materials usually had oneend initially open, to be closed only after filling. Apart from thenecessity of closing such bags, e.g., by folding and stapling, byWelding, or by the use of adhesives or cords, such bags must bedistended before filling because they are made and transported in fiatcondition.

It would be desirable to avoid the operations of distending the bagprior to lling and of sealing after filling, and much time can be savedby simply pushing a filling nozzle or spout into the bag and introducingthe material through the nozzle. This would present a great advantageparticularly when subdivided material, such as cement, flour, grain orfertilizer are packaged, both by saving time and operations and byreducing dust in the atmosphere. Prior attempts to attain this resulthave not been technologically successful.

A desirable characteristic of such a valve structure for filling a bagis that the valve be applied to a fiat part of the bag, so that the bagscan be manufactured and stored in flat condition before use. It isessential that such a valve be economical. Further, it is desirable thatsuch a valve structure can be applied to the bag with a minimum waste ofthe plastic material of Which the bag is formed.

Plastic bags are often formed of tubular stock which may include a seambut, more usually, is in the form of a sock, which is a seamless tubeextruded from a die and inflated until it has the requisitecircumferential dimension and is cooled, and thereafter pressed fiatlyand Wound as a double layer on a roll. Much of such stock is wasted byoverlaps of the fioor that includes overlapping flaps and, moreover,according to known constructions may be reinforced by an insert.

Further, it is often desirable to permit air or other gas to seep outslowly from the bag while essentially confining the solid materials.This permits the escape of air that may be introduced into the bag withthe goods or formed from the goods and which, if not relieved, can bloatthe bag and/or give it poor stackability.

The principal object of the invention is to provide a bag of plasticmaterial having a part thereof that forms a bounding Wall of the bagformed as a valve structure which is adapted to receive a filling nozzleor spout through which material can be introduced, said valve beingself-closing to prevent the escape of material from the bag. Ancillarythereto, it is desired to form the valve so that it may lie fiat whenthe bag is folded or collapsed; and/ or to construct it for the facileinsertion of the lling nozzle; and to provide a valve that seals the bagto prevent entry of moisture, either as a liquid or as aircarried Watervapor.

A further object is to provide a valve structure that f ICC permits theescape of air or gas from the bag, to the exclusion of solid materialswithin the bag.

Still another object is to attach the valve to the bag in a manner thatinsures structural stability and security against leaks while avoidingWaste of plastic material, especially the stock that is used to form theside body of the bag. Ancillary ther'eto, it is an object to mount thevalve so as to constitute a transverse Wall or fioor when the bag isdistended, said wall or floor being folded against and parallel to thefiat side body when the bag is folded.

In summary, the plastic bag according to the invention includes aperipherally closed side body of plastic material, e.g., made of a tube,and has at least one closed end and a valve structure that includes aplurality of juxtaposed sheets or layers of plastic material of which atleast the innermost is flexible, formed with displaced incisions so asto provide juxtaposed portions of said sheets between the incisions thatlie in sealing relation save during filling of the bag, said valvestructure being attached in sealed relation to a suitable part of theside body and forming a bounding part of the bag.

A filling nozzle can be inserted into the incision in the outermostsheet to separate the said juxtaposed sheet portions, and material canbe injected into the bag through the nozzle and the several incisions.When the nozzle is withdrawn, the valve closes by the engagement of thesaid juxtaposed sheet portions, which are forced into sealing engagementby the force of solid material within the bag against the innermost ofsaid layers, thereby preventing escape of solid material.

It is evident that both ends of the bag may be initially closed, savefor the said valve structure, whereby no sealing or bag-closingoperation is necessary after the bag is filled. When the bag is thusinitially closed except for the valve, the latter is advantageouslysituated at or near the top of the bag, e.g., forming the upper endclosure thereof. However, the invention is further conf cerned with thevalve construction to be described and such a valve is applicable alsoto bags having an end that is initially open and which is closed bysuitable means before filling, or which is closed after filling, thenozzle and valve being then used merely to inject a blast of air intothe bag to distend it and facilitate loading.

In another aspect, the invention resides in a valve structure that formsa transverse, foldable Wall of the bag at an end thereof. This is usefulparticularly when the bag is of the type having a rectangular crosssection and has a foldable fioor at one end. When such a bag iscollapsed, it is folded along one or along three parallel, verticalcrease lines at each end and the rectangular floor or transverse walltogether with a triangular-shaped part of the bag side wall, situated ateach end of said rectangular floor or wall, is folded to lie parallel tothe juxtaposed side walls of the folded bag (the said triangular partsforming parts of the bag end Walls when the bag is distended). Theconstruction according to the preceding paragraph effects an economy inthe use of plastic material. This economy is enhanced by forming the bagside body with narrow flaps that project from the end of the bag sidewalls between the said triangular parts and lie fiatly against themarginal parts of the valve in non-overlapping relation, to leave amajor part of the valve sheets uncovered.

The advantage of this construction lies in the fact that a much shorterlength of the tubular stock is required to construct the side wall andits connecting appendages for forming the transverse w-all or fioor thanin conventional constructions that provide fold-over floors: only verynarrow flaps project beyond the ends of the side body,

in contrast to the wide over-lapping Lbase flaps commonly used to form afloor, and the transverse wall is formed essentially by -the sheets ofthe valve.

The innermost sheet of the valve structure may be formed of thinnermaterial than the other foils and may have a width greater than thevalve structure to provide marginal strips, suitably having widths equalto the said flaps on the bag side body, that are folded about themargins of the other sheet or sheets of the valve and lie atly againstthe marginal parts of the outermost sheet and are situated between saidmarginal parts and the said flaps; the ends of all sheets of the valvestucture then lie inwardly of the said triangular parts of the bag. Theseveral parts mentioned are interconnected in sealed relation to the bagside body by any suitable means, usually by weldments. The term weldingis used herein to denote the formation of a seal by the application ofheat, if desired together with pressure, causing the thermoplasticmaterials to unite. However, other sealing imeans, such as theapplication of adhesives or strips of tacky and chemically similarstrips of plastic material, are contemplated. When adhesives are usedthey must usually be applied in heated condition and the means forapplying them must also be heated.

In a preferred embodiment the valve structure comprises three juxtaposedsheets of which the two outer sheets are formed from the same tube ofplastic material (usually seamless) that is creased and pressed atly tobring the opposite parts into flat engagement. Each of these parts hasan incision, and the incisions in the said parts may be mutuallydisplaced and situated so that the incision formed in the intermediatesheet lies longitudinally between the incisions in the innermost andoutermost sheets. The foil of which such a tube is formed can beconsiderably thinner than the foil used for a single outer sheet andcan, further. lbe Imore easily worked into the lbag to form an end wall.Further, the incisions in the two outer layers, when offset, provide anadditional valve that seals the bag when the said layers close on eachother by juxtaposition of the parts between the said displacedincisions.

To permit air to escape from the bag after lling, for the purpose ofpreventing a bloated outline and for facilitating stacking the filledbags with reduced tendency to slip on each other, according to theinvention the valve may be provided with an air-escape passageway thatis preferably restricted and/or tortuous, so that only a slow seepage ofair occurs and the entrainment of ne solid materials is minimized orwholly prevented lby the size of the passageway, In a specificembodiment to be described, utilizing the three-layer valveconstruction, the two inner sheets of the valve are sealed to oneanother, e.g., welded along a transverse line at one side of both of theincisions in the two inner sheets, to isolate a space that is situatedbetween bounding parts of said sheets, and the innermost sheet hasperforations through which air can enter the said space from the bag.The said perforations are advantageously small, eg., smaller than theparticles of solids contained Within the bag, if this is feasible. Thesaid isolated space communicates with the outside of the bag through apassageway that extends about the longitudinal margin of the two outervalve sheets at least at one side thereof and thence longitudinallybetween the outer face of the outermost sheet and the marginal striptrip of the innermost sheet (or, when such a strip is not provided, theHap of the bag side body) -along the laterally outer side of themarginal weld seam or seal line, the said seam or seal line beingdisplaced inwardly from said margin of the valve sheets. Thelongitudinal channel thus provided between the seam and the edge is openat the end near one or both of said triangular parts of the bag.

The incisions are prefera'bly substantially parallel slits that extendtransversely across the sheets. Simple cuts, not involving the removalof any sheet material, are preferred for all incisions save that in theoutermost sheet; the latter may be fonmed to provide a lip that isfolded over on itself from the incision edge nearer the other incisionsand is secured in flat engagement with the outermost sheet. The lipthereby reinforces the outer sheet at the incision and gives a nitewidth to the incision, which facilitates insertion of the fillingnozzle.

To aid in guiding the filling nozzle through the several displacedincisions or slits, that edge of each incision in each sheet except theoutermost which is remote from the incision in the outermost sheet isstructurally connected to the next outer sheet, e.g., by a weld seam.This connection prevents the nozzle from overshooting or entering thedead pocket between the juxtaposed sheets beyond the incision or, when ashorter nozzle is inserted, aids in the ow of the material dischargedtherefrom into the proper incision and, therethrough, into the bag.

The invention will be further described with reference -to theaccompanying drawings forming a part of this specification and showingtwo preferred embodiments, wherein:

FIGURE l is a perspective view of a .part of a Ibag with the end portionfolded, prior to applying the valve structure thereto;

FIGURE 2 is a plan of the bag end with the valve structure partlyaiiixed, before folding the flaps;

FIGURE 3 is a longitudinal section taken on the line 3-3 of FIGURE 2;

FIGURE 4 is a plan of the completed bag and valve;

FIGURE 5 is a fragmentary transverse section taken on the line 5*5 ofFIGURE 4;

FIGURE 6 is a plan of a completed bag and valve showing anotherembodiment which uses three sheets;

FIGURE 7 is -a longitudinal section taken on the line 7-7 of FIGURE 6;

FIGURE 8 is a transverse section taken on the line 8-S of FIGURE 6;

FIGURE 9 is an enlarged fragmentary plan of a part of FIGURE 6; and

FIGURE 10 is a bottom plan of the valve, viewed from the interior of thebag.

In the several views the sheets of plastic material are shown by heavysolid lines and shown separated, for clarity, and the weldments areindicated in section lby xs and in plan lby parallel lines extending theweldment seams. It will be understood that these representations areonly to indicate the construction, and that in practice the sheets areflatly juxtaposed and the weldments occupy no space,

FIGURE 1 shows the upper part of a bag formed of a tube 11 ofthermoplastic material of width W (half circumference) terminating at anupper edge 12 which lies in a plane perpendicular to the tube axis, saidtube forming the side ybody of the bag and including triangular parts13, 14. The tube 11 is shown creased at diametrically opposed, verticallines 15 meeting the outer apices of the triangles; this brings theopposite sides of the body together flatly along a line 16. It will beunderstood that it is also possible to fold the bag on other lines;thus, in manufacture the bag normally includes convex creases along thechained lines 17 which terminate at the inner apices of the triangles,and concave creases at the lines 15, such folding being well understoodin the art of bagmaking. The marginal parts of the side body providenarrow aps 18, 19, demarcated by chain lines, the said chain lines beingthe fold lines described hereinafter.

Referring to FIGURES 2-5, the valve structure forms a transverse wall atthe upper end of the bag and comprises an outer, preferably thick sheet29 of plastic material which has the same width as the finished valve,i.e. equal to the distance between the chained fold lines of the aps 18,19, in FIGURE 1. The valve further comprise an inner sheet 21,preferably of a very thin foil, having the same length as the sheet 20but wider to provide marginal strips 22, 23, of widths equal to theflaps 18, 19, respectively. Both sheets and 21 underlie the margins ofthe triangular part-s 13, 14, as is shown in FIGURE 3, the ends of thesesheets being pushed into place. The ends of these sheets are then sealedto said triangular parts, e.g., by applying heat, if desired togetherwith pressure, along seams 24, 25, which extend transversely across thesheets. It will be noted that these seams provided weldments that jointogether three juxtaposed layers of plastic.

The outer sheet 20 is, prior to assembly, formed with a transverseincision 26 which is shaped to provide a lip 27 that is folded over onitself and is structurally secured to lie flatly against the sheet by aweld seam 28. Thereby the incision 26 has a substantial width and itsedge at the lip 27 is reinforced against damage lwhen engaged by thenozzle. The inner sheet 21 is, prior to assembly to the bag, formed witha transverse incision 29 that is displaced from the incision 26 when thesheets are assembled. Although for clarity the incision 29 is shown tohave a finite width, in the preferred device it is simply a cut withoutremoval or folding of material. The sheets 20 and 21 are structurallyjoined, either before or after assembly to the `bag 11, by a transverseweld seam 30 at the edge of the incision 29 that is remote from theincision 26.

After applying the seams 24, 25, the flaps 18, 19 are folded, togetherwith the strips 22, 23, to cause the latter to lie atly against t-heouter face of the outer sheet 20, as appears in FIGURES 4 and 5. Seals,such as weldments along seams 31, 32, are applied to join together thefour juxtaposed sheets. These seams extend the full length of the valvesheets between the triagular portions 13, 14.

In use, assuming the lower end of the bag (not shown) to be closed, andthe bag to be initially in empty, collapsed condition, a filling nozzle(not shown), connected to suitable supply means for the material to bepackaged, is inserted into the incision 26, thereby separating the sheetportions 20 and 21' situated between the incisions 26 and 29 to permitthe material to enter the bag through the latter and gradually distendit. When the nozzle is of sufficient length it extends into the bag. Theseam 30 insures passage of the material-and also of the nozzle, if longenoughinto the incision 29 without entry into the inter-layer spacebeyond the incision. When the bag is lled to the desired extent thenozzle is withdrawn `and the said portions 20 and 21 move together intollat juxtaposition to seal t-he bag, this sealing action being aided bythe pressure of the contents of the bag against the inner sheet. Thisseal further prevents entry `of moisture, liquid as well as air-carriedmoisture vapor, into the bag where it could damage the contents, such ascement or hygroscopic material.

The construction shown in FIGURES 6-10 differs from the foregoing inthat the valve structure comprises, instead of a lsingle, relativelythick outer foil, a plurality of thinner sheets formed from a singletube of plastic material `which is preferably seamless; further, thisembodiment includes the optional air-escape means. Reference numbers11-14, 18 and 19 denote part previously described. The two outer layers33, 33a, are flatly pressed, opposite sides of the samepplastic tu-becreated along diametrically opposite lines as appears in FIGURE 8, andformed with longitudinally displaced, slit-shaped transverse incisions26a and 34. The former is formed with a lip 27a, folded over on itselfand secured by a seam 28a; the latter is preferably merely a cut, madewithout removal or folding of material. The innermost sheet 21a has theoutline previously described for the sheet 21, having marginal strips22a and 23a, which are folded about the creases of the tube to lieflatly against the outer face of the sheet 33, inside of the flaps 18,19. The sheet 21a has a transverse slit-shaped incision 29a, formed asdescribed above for the incision 29. The incision 26a, 34 and 29a aremutually displaced and arranged in the order stated.

Each pair of juxtaposed sheets are structurally interconnected on thesides of the incisions 34 and 29a remote from the incision 26a by weldseams 35 and 30a, to facilitate passage of the filling nozzle andmaterial into the bag. Consequently the nozzle can be pushed through theincision 26a and thence through the incisions 34 and 29a while the seams35 and 30a insure the proper direction, as previously described.

The stack of three sheets is vconnected to the side body 11 bytransverse end seams 24a, 25a, and longitudinal seams 31a, 32a,corresponding to the seams 24, 25, 31 and 32 and similarly formed.However, in this embodiment, when the air-escape feature is used, asdescribed below, at least one, and preferably, both seal seams 31a and32a are positioned inwardly from the outer longitudinal margins of thevalve sheets to provide a longitudinal channel 37 between the seam orseams and the margin or margins, said channel being open at the endthereof toward the triangular part 13, asfshown by the arrow 36 inFIGURE 9 (and also, if desired, at the other end toward the triangularpart 14). This channel is indicated at 37 in FIGURE 8, and extendsbetween the underside of the strip 22a (and 23a, if desired) and theouter face of the sheet 33. It may be noted that, as is indicated inFIGURE 8, the weldment seams 31a and 32a interconnect only the ap 18 (or19), strip 22a (or 23a) and the outer most sheet 33; connection to thesheet 33a is optional `but not necessary, while the latter sheet and theunderlying sheet 21a are preferably avoided at least in part to providean air-escape passage.

The valve according to the second embodiment operates in the mannerpreviously described save that it provides two valves in series. Thus,when the iilling nozzle is withdrawn, the parts of the sheets 21a and33a between the incisions 29a and 34 move into juxtaposition; similarly,the parts of the sheets 33a and 33 between the incisions 34 and 26a moveinto juxtaposition. Both are aided in their sealing actions to preventescape of materials by the pressure exerted outwardly against the sheet21a by the said materials.

To permit air to escape from the bag, there is provided a transverseseal seam, such as the seam 38, extending fully across the valve whichinterconnects the two inner sheets 21a and 33a to one side of both theincisions 29a and 34, to isolate a space between the said sheets on theside of the seam 38 away from said incisions. A plurality of holes 39 isformed in the sheet 21a to establish communication between the interiorof the bag and the said space. cation with the outside by one or moretortuous passageways extending about the margins of the sheet 33a to thelongitudinal channel(s) 37 (FIG. 8) and the end opening(s) 36 (FIG. 9).The holes 39 permit gas to enter the said isolated space to effect aslight and localized separation between the sheets 21a and 33a. Theholes 39 may be made small enough to prevent the passage of solidmaterial; however, in the case of nely powdered material such as cementreliance is had on the slow movement or seepage of air, which entrainsonly a negligible amount of powder which, further, is trapped by thetortuous passageway, so that little or no powder escapes to the outside.When the solid material presses against the part of the sheet containingthe holes 39 little seepage of air occurs.

It is evident that while the incisions 26a, 34 and 29a are large topermit rapid lling of the bag, the holes 39 and its connecting exitpassages are restricted.

Further, certain seams were shown to interconnect only some of thejuxtaposed layers or sheets. For example, the seams 31a and 32a do notconnect the innermost sheet 21a to the sheet 33a, and the transverseseam 38 does not connect any sheet above the sheet 33a. Such seams canbe made by inserting implements that lie adjacently to the stack ofsheets to be welded together, while applying pressure thereto, the saidimplements hav- The said space is in communiing only the sides thereofnext to said stack heated, so that any sheet adjacent to the unheatedface of the implement is not heated sufiiciently to bring it to thefusion or softening temperature and, moreover, the absence of pressurewill prevent thel formation of a tight seal.

We claim as our invention:

1. A bag of plastic material having a peripherally closed side body andan end closure, at least a part of said bag being formed as a valvestructure for the insertion of a filling nozzle, said valve structureincluding:

(a) at least two parallel, juxtaposed sheets of plastic material thatconstitute a terminal part of said bag, are separate from said sidebody, and are sealed to said body,

(b) each of said sheets being formed with an incision, the incisions indifferent sheets being displaced from each other so that the sheetportions between incisions in different sheets lie in flat, juxtaposedrelation to form a seal against the escape of material from the bag,

(c) the incision in the outermost sheet being accessible to the outsideof the bag for the insertion into the incision therein of a fillingnozzle to separate the said portions for introducing said material intothe bag through the incisions, and

(d) the end of said side body which is adjacent to said terminal wallincluding a pair of narrow fiaps that lie flatly against and are insealed relation to the outside of said terminal wall and are inlaterally spaced relation to each other.

2. A bag as defined in claim 1 wherein the innermost of said sheets isthinner than said outermost sheet, has a width greater than the width ofsaid terminal wall, and includes marginal strips that extend about themargins of the outermost sheet and lie in fiat engagement with the outerface thereof between said outer face and the inner faces of said aps,the said fiaps, marginal strips and outermost sheet being mutuallysealed.

3. A bag as defined in claim 1 wherein said incisions are elongatedslits extending'transversely to the axis of displacement of saidincisions and the innermost sheet is structurally connected to theadjacent sheet along the edge of the slit in the innermost sheet that isremote from the slit in the outermost sheet.

4. A bag as defined in claim 1 wherein said incision in the outermostsheet is an elongated slit having that edge thereof which is nearer tothe incision in the innermost sheet formed as a lip, said lip being bentover on itself and being structurally secured to said outer sheet infiat relation thereto for reinforcing the said slit.

5. A bag of plastic material having a peripherally closed side body andan end closure, at least a part of said bag being formed as a valvestructure for the insertion of a filling nozzle, said valve structureincluding:

(a) at least two parallel, juxtaposed sheets of plastic material thatconstitute a bounding part of said bag and are sealed to said body,

(b) each of said sheets being formed with an incision, the incisions indifferent sheets being displaced from each other so that the sheetportions between incisions in different sheets lie in fiat, juxtaposedrelation to form a seal against the escape of material from the bag,

(c) the incision in the outermost sheet being accessible to the outsideof the bag for the insertion into the incision of a filling nozzle toseparate the said portions for introducing said material into the bagthrough the incisions,

(d) means including the innermost of said sheets delining an enclosedspace, said innermost sheet having at least one small aperture formedtherein for the fiow of gas from the interior of the bag into saidenclosed space, and

(e) a passageway formed in said bag interconnecting the said enclosedspace with the outside of the bag.

6. A bag as defined in claim 5 wherein:

(a) the said sheets constituting the valve are sealed to the side bodyalong seal seams at least one of which is situated inwardly from themargin of the sheets and leaving between said margin and said seam apassage that is open to the outside of the bag, and

(b) said enclosed space is in communication with the said passage by apath that constitutes a part of said passageway.

7. A bag as defined in claim 5 wherein the said valve structure includesat least three sheets of plastic material, the said enclosed space beingbounded by the innermost sheet and the sheet adjacent thereto.

8. A bag as defined in claim 1 wherein said valve structure comprisesthree juxtaposed sheets of plastic material, each of said sheets havingan incision formed as an elongated slit extending transversely to theline joining said incisions, said slits being situated at progressivelydisplaced positions to provide between each pair of adjacent incisionsjuxtaposed sheet portions to form seals.

9. A bag of plastic material having a peripherally closed side body andan end closure, at least a part of said bag being formed as a valvestructure for the insertion of a filling nozzle, said valve structureincluding:

(a) at least three juxtaposed sheets of plastic material that constitutea bounding part of said bag and are sealed to said body, the two outerof said sheets being formed of a single tube of plastic material havingthe opposite parts thereof pressed fiatly against each other and beingintegrally joined at the lateral edges thereof,

(b) each of said three sheets being formed with an incision, the saidincisions being displaced from each other so that the incision in theinnermost and outermost lsheets are on opposite sides of the incision inthe intermediate sheet, to provide portions of juxtaposed sheets betweeneach pair of incisions that lie in fiat, juxtaposed relation to formseals against the escape of material from the bag, and

(c) the incision in the outermost sheet being accessible to the outsideof the bag for the insertion into the bag of a filling nozzle toseparate the said juxtaposed portions for introducing material into thebag through the said incisions.

10. A bag as defined in claim 9 wherein said incisions are elongated,substantially parallel slits and each pair of juxtaposed sheets isstructurally interconnected along that edge of the slit in therelatively inner sheet of the respective pair which is remote from ytheincision in the outermost sheet.

11. A bag as defined in claim 9 wherein:

(a) said incisions are elongated and extend transversely across saidsheets,

(b) the innermost and intermediate sheets are mutually sealed along atransverse line situated to one side of both the incisions in theinnermost and intermediate sheets to isolate a space that is enclosed bybounding parts of the mutually sealed sheets situated on the said sideof the transverse seal line,

(c) said bounding parts of the innermost sheet being formed with smallperforations extending therethrough for admitting air from the bag intothe said space, and

(d) said space being in communication with the outside of the bag by apassageway that extends about at least one of said lateral edges of thetube forming the two outermost sheets.

12. A bag as defined in claimv 11 wherein:

(a) said bag side body includes at one end thereof which is adjacent tosaid valve structure a pair of narrow, lateral aps situated outwardlyfrom said outermost sheet at the lateral margins thereof and in parallelrelation to said lateral edges of the tube lthat constitutes the twooutermost sheets, and

(b) said aps are sealed to said outermost sheets along marginal seallines at least one of which is displaced inwardly from the respectivelateral edge, the longitudinal space between the said seal line and thepart of the ap adjoining the bag valve immediately outward from saidoutermost sheet being open to the outside of the bag,

(c) whereby said passageway between the space dened in paragraph (b) 1ofclaim 11 and the outside extends about the outside of at least one ofsaid lateral edges and thence through the said longitudinal space.

13. A bag as defined in claim 12 wherein:

(a) said sheets constitute a terminal wall of the bag and are situatedtransversely to the axis of said side body,

(b) said innermost sheet has a width greater than the Width of the outersheets and includes marginal strips that extend about the said lateraledges and References Cited by the Examiner UNITED STATES PATENTS3,195,801 7/ 1965 Symons et al. 229-625 3,197,119 7/ 1965 Hartig et al229-625 3,201,029 8/ 1965 Batosti et al. 229-625 3,220,635 11/ 1965Kasting et al. 229-625 FOREIGN PATENTS 861,352 12/1952 Germany.

20 JOSEPH R. LECLAIR, Primary Examiner.

DAVID M. BOCKENEK, Examiner.

1. A BAG OF PLASTIC MATERIAL HAVING A PERIPHERALLY CLOSED SIDE BODY ANDAN END CLOSURE, AT LEAST A PART OF SAID BAG BEING FORMED AS A VALVESTRUCTURE FOR THE INSERTION OF A FILLING NOZZLE, SAID VALVE STRUCTUREINCLUDING: (A) AT LEAST TWO PARALLEL, JUXTAPOSED SHEETS OF PLASTICMATERIAL THAT CONSTITUTE A TERMINAL PART OF SAID BAG, ARE SEPARATE FROMSAID SIDE BODY, AND ARE SEALED TO SAID BODY, (B) EACH OF SAID SHEETSBEING FORMED WITH AN INCISION, THE INCISIONS IN DIFFERENT SHEETS BEINGDISPLACED FROM EACH OTHER SO THAT THE SHEET PORTIONS BETWEEN INCISIONSIN DIFFERENT SHEETS LIE IN FLAT, JUXTAPOSED RELATION TO FORM A SEALAGAINST THE ESCAPE OF MATERIAL FROM THE BAG, (C) THE INCISION IN THEOUTERMOST SHEET BEING ACCESSIBLE TO THE OUTSIDE OF THE BAG FOR THEINSERTION INTO THE INCISION THEREIN OF A FILLING NOZZLE TO SEPARATE THESAID PORTIONS FOR INTRODUCING SAID MATERIAL INTO THE BAG THROUGH THEINCISIONS, AND (D) THE END OF SAID SIDE BODY WHICH IS ADJACENT TO SAIDTERMINAL WALL INCLUDING A PAIR OF NARROW FLAPS THAT LIE FLATLY AGAINSTAND ARE IN SEALED RELATION TO THE OUTSIDE OF SAID TERMINAL WALL AND AREIN LATERALLY SPACED RELATION TO EACH OTHER.